Same taste with zero calories. Those five words have had a great impact on soda consumption since the original Coca-Cola was introduced in 1886. Although Coke and Pepsi have always dominated the top two spots in sales (#1 and #2 respectively), last year Diet Coke unseated Pepsi for the number 2 spot, confirming the popularity of diet and light beverages.

The rise of calorie-free drinks leads to curiosity about how they differ.

“The main difference between diet and regular soda is the removal of sugars and addition of artificial sweeteners instead,” said Jeanette Andrade, graduate assistant at McKinley Health Center and registered dietitian. “(Diet soda) tastes as sweet as sugar but has no calories or carbohydrates.”

The main ingredient that gives regular soda its sweetness is high fructose corn syrup (HFCS). It is made from glucose and fructose and is extracted from the starch found in corn.

Since HFCS is a carbohydrate, it contains a lot of energy and contributes to the high caloric value of regular soda. In diet versions, however, aspartame is substituted.

“This substance has a very small amount of calories compared to table sugar or HFCS,” said Manabu Nakamura, associate professor of nutrition. “You only need a very small amount of it to get the same level of sweetness found in regular drinks.”

Aspartame is around 200 times sweeter than sucrose; therefore they use a trivial amount to get the same sweetness. By putting in very little, you get the “zero” calories on the bottles. The taste of aspartame and other artificial sweeteners differs from that of table sugar in how long the sweetness lasts, though aspartame comes closest to sugar’s taste profile among the various artificial sweeteners.

Some people have raised concerns about the possible negative effects of these sweeteners. Rebecca Roach, teaching assistant in ACES, emphasizes the safety of these products and that they have been rigorously tested by various agencies.

“They’ve all been checked out by the FDA, USDA and all the other people that check on the safety of our food,” Roach said. “They’ve all been recognized as appropriate uses for dietary intake.”

Sweeteners are not the only thing added to carbonated beverages. Many other ingredients are put in to give them their distinct color and flavor.

“Other ingredients include carbonated water, dyes (and) acids to stabilize the solution, and phosphoric acid to sharpen the flavor,” Andrade said. “Some studies have suggested that consuming a lot of soda may lead to brittle bones. That is because of the phosphoric acid amount found in these drinks.”

Although phosphorous is an important bone mineral, disproportionate amounts of it compared to calcium can be harmful. This is because maintaining a one-to-one balance between calcium and phosphorus is the ideal way. Calcium is released from our teeth and bones into our bloodstreams to help balance the phosphoric acid in the pop we drink. Eventually the phosphoric acid is excreted, taking with it the released calcium. This calcium deficiency may lead to soft teeth and weaker bones.

Aside from that, soda usage is pretty safe, whether regular or diet.

“There are no major health concerns from the chemicals used in the soda,” Nakamura said. “But the main concern is the amount of calories found in regular soda.”

Indeed, regular Coke and Pepsi can contain as much as 65g of sugar per serving (20 oz bottle). So switching to a calorie-free alternative might seem like the best thing to do in order to keep the pounds away. That claim, however, is not necessarily true.

“Certainly diet doesn’t hurt (because it has no calories),” Nakamura said. “But at the same time, there is no clear demonstrated benefit in terms of weight loss from switching from regular to diet either.”

This might sound odd at first. Usually, cutting back on calories is a good way to shave off the extra pounds. But Professor Nakamura explains that the tongue tastes sweetness, and sweet taste is among the best taste often associated with positive emotion (unlike bitter or sour foods). When a person tastes sweetness, it immediately signals there are nutrients and carbohydrates in the food. So you are calibrated to associate sweetness with energy.

“The problem arises when there is sweet taste but no energy to fill up the stomach,” Nakamura said. “Switching to diet is basically fooling the taste buds. You taste the sweetness but don’t feel full afterwards.”

This might lead a person to eat more since they never got the energy needed, and the cravings get more intense. He notes that this is only a possibility, but still a logical one.

“Soda, being a liquid, is easily over-consumed in comparison to solid foods like sweets and cookies,” Nakamura said. “This is pretty well-established that when you are given the same amount of calories in a regular meal or liquid form, people will over-consume the liquid counterpart.”

Roach reiterated the fact that diet drinkers don’t necessarily cut back on calories in other aspects of their diet. Just drinking diet soda will not automatically mean weight loss.

So the next time you want to grab the diet coke, remember that you may over-consume calories even if they’re not from the soda. The best option is to stay with water, which is the natural choice for keeping hydrated and healthy.

“If you are going to drink diet or regular, make sure you have sips of water in between,” Andrade said. “But as always, water is the best choice.”